Here's what Martin said:
"Sphinx listens on two ports, 9306 for SQL (which is what the web client
queries) and 9312 for its own Sphinx internal protocol, which is what the
distributed agents use."
So we should just be changing this:
listen = 0.0.0.0:9306:mysql41
listen = 0.0.0.0:3307
to this:
listen = 0.0.0.0:9306:mysql41
listen = 0.0.0.0:9312